X^2-Y^2+6X+10Y-30=0 X^2+Y^2-5X-8Y+21=0 X=?Y=?
【2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2】/2(x-y)^2=
已知x*x+4x+y*y-2y+5=0,则x*x+y*y=?
已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y)
若(x*x+y*y)(x*x+y*y)-4x*x*y*y=0,求代数式(x*x+5xy+y*y)/(x*x+2xy+y*
设Z=X+Y,其中X,Y满足X+2Y>=0,X-Y
6(x-y)-2(x+y)=14 3(x-y)+(x+y)=5
已知x.x+y.y+8x+6y+25=0,求代数式(x.x-4y.y)/(x.x+4xy+4y.y)-x/(x+2y)的
[x(x-y)-y(x-y)+(x+y)(x-y)]÷2x其中x=2012 y=2013
已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值?
(4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuai
设x>1,y>0,若x^y+x^-y=2根号2,则x^y-x^-y等于
变量x,y满足x-2y=0,x